* [PATCH bpf-next 0/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca @ 2020-03-19 23:49 Martin KaFai Lau 2020-03-19 23:50 ` [PATCH bpf-next 1/2] " Martin KaFai Lau 2020-03-19 23:50 ` [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage " Martin KaFai Lau 0 siblings, 2 replies; 6+ messages in thread From: Martin KaFai Lau @ 2020-03-19 23:49 UTC (permalink / raw) To: bpf; +Cc: Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev This set adds bpf_sk_storage support to bpf_tcp_ca. That will allow bpf-tcp-cc to share sk's private data with other bpf_progs and also allow bpf-tcp-cc to use extra private storage if the existing icsk_ca_priv is not enough. Martin KaFai Lau (2): bpf: Add bpf_sk_storage support to bpf_tcp_ca bpf: Add tests for bpf_sk_storage to bpf_tcp_ca net/ipv4/bpf_tcp_ca.c | 33 +++++++++++++++++++ .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 28 ++++++++++++++-- tools/testing/selftests/bpf/progs/bpf_dctcp.c | 16 +++++++++ 3 files changed, 74 insertions(+), 3 deletions(-) -- 2.17.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH bpf-next 1/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca 2020-03-19 23:49 [PATCH bpf-next 0/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca Martin KaFai Lau @ 2020-03-19 23:50 ` Martin KaFai Lau 2020-03-20 3:39 ` Yonghong Song 2020-03-19 23:50 ` [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage " Martin KaFai Lau 1 sibling, 1 reply; 6+ messages in thread From: Martin KaFai Lau @ 2020-03-19 23:50 UTC (permalink / raw) To: bpf; +Cc: Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev This patch adds bpf_sk_storage_get() and bpf_sk_storage_delete() helper to the bpf_tcp_ca's struct_ops. That would allow bpf-tcp-cc to: 1) share sk private data with other bpf progs. 2) use bpf_sk_storage as a private storage for a bpf-tcp-cc if the existing icsk_ca_priv is not big enough. Signed-off-by: Martin KaFai Lau <kafai@fb.com> --- net/ipv4/bpf_tcp_ca.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c index 574972bc7299..0fd8bfde2448 100644 --- a/net/ipv4/bpf_tcp_ca.c +++ b/net/ipv4/bpf_tcp_ca.c @@ -7,6 +7,7 @@ #include <linux/btf.h> #include <linux/filter.h> #include <net/tcp.h> +#include <net/bpf_sk_storage.h> static u32 optional_ops[] = { offsetof(struct tcp_congestion_ops, init), @@ -27,6 +28,27 @@ static u32 unsupported_ops[] = { static const struct btf_type *tcp_sock_type; static u32 tcp_sock_id, sock_id; +static int btf_sk_storage_get_ids[5]; +static struct bpf_func_proto btf_sk_storage_get_proto __read_mostly; + +static int btf_sk_storage_delete_ids[5]; +static struct bpf_func_proto btf_sk_storage_delete_proto __read_mostly; + +static void convert_sk_func_proto(struct bpf_func_proto *to, int *to_btf_ids, + const struct bpf_func_proto *from) +{ + int i; + + *to = *from; + to->btf_id = to_btf_ids; + for (i = 0; i < ARRAY_SIZE(to->arg_type); i++) { + if (to->arg_type[i] == ARG_PTR_TO_SOCKET) { + to->arg_type[i] = ARG_PTR_TO_BTF_ID; + to->btf_id[i] = tcp_sock_id; + } + } +} + static int bpf_tcp_ca_init(struct btf *btf) { s32 type_id; @@ -42,6 +64,13 @@ static int bpf_tcp_ca_init(struct btf *btf) tcp_sock_id = type_id; tcp_sock_type = btf_type_by_id(btf, tcp_sock_id); + convert_sk_func_proto(&btf_sk_storage_get_proto, + btf_sk_storage_get_ids, + &bpf_sk_storage_get_proto); + convert_sk_func_proto(&btf_sk_storage_delete_proto, + btf_sk_storage_delete_ids, + &bpf_sk_storage_delete_proto); + return 0; } @@ -167,6 +196,10 @@ bpf_tcp_ca_get_func_proto(enum bpf_func_id func_id, switch (func_id) { case BPF_FUNC_tcp_send_ack: return &bpf_tcp_send_ack_proto; + case BPF_FUNC_sk_storage_get: + return &btf_sk_storage_get_proto; + case BPF_FUNC_sk_storage_delete: + return &btf_sk_storage_delete_proto; default: return bpf_base_func_proto(func_id); } -- 2.17.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH bpf-next 1/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca 2020-03-19 23:50 ` [PATCH bpf-next 1/2] " Martin KaFai Lau @ 2020-03-20 3:39 ` Yonghong Song 0 siblings, 0 replies; 6+ messages in thread From: Yonghong Song @ 2020-03-20 3:39 UTC (permalink / raw) To: Martin KaFai Lau, bpf Cc: Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev On 3/19/20 4:50 PM, Martin KaFai Lau wrote: > This patch adds bpf_sk_storage_get() and bpf_sk_storage_delete() > helper to the bpf_tcp_ca's struct_ops. That would allow > bpf-tcp-cc to: > 1) share sk private data with other bpf progs. > 2) use bpf_sk_storage as a private storage for a bpf-tcp-cc > if the existing icsk_ca_priv is not big enough. > > Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Yonghong Song <yhs@fb.com> ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage to bpf_tcp_ca 2020-03-19 23:49 [PATCH bpf-next 0/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca Martin KaFai Lau 2020-03-19 23:50 ` [PATCH bpf-next 1/2] " Martin KaFai Lau @ 2020-03-19 23:50 ` Martin KaFai Lau 2020-03-20 3:49 ` Yonghong Song 1 sibling, 1 reply; 6+ messages in thread From: Martin KaFai Lau @ 2020-03-19 23:50 UTC (permalink / raw) To: bpf; +Cc: Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev This patch adds test to exercise the bpf_sk_storage_get() and bpf_sk_storage_delete() helper from the bpf_dctcp.c. Signed-off-by: Martin KaFai Lau <kafai@fb.com> --- .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 28 +++++++++++++++++-- tools/testing/selftests/bpf/progs/bpf_dctcp.c | 16 +++++++++++ 2 files changed, 41 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c index 8482bbc67eec..9aaecce0bc3c 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c @@ -11,6 +11,7 @@ static const unsigned int total_bytes = 10 * 1024 * 1024; static const struct timeval timeo_sec = { .tv_sec = 10 }; static const size_t timeo_optlen = sizeof(timeo_sec); +static int expected_stg = 0xeB9F; static int stop, duration; static int settimeo(int fd) @@ -88,7 +89,7 @@ static void *server(void *arg) return NULL; } -static void do_test(const char *tcp_ca) +static void do_test(const char *tcp_ca, const struct bpf_map *sk_stg_map) { struct sockaddr_in6 sa6 = {}; ssize_t nr_recv = 0, bytes = 0; @@ -110,6 +111,14 @@ static void do_test(const char *tcp_ca) return; } + if (sk_stg_map) { + err = bpf_map_update_elem(bpf_map__fd(sk_stg_map), &fd, + &expected_stg, BPF_NOEXIST); + if (CHECK(err, "bpf_map_update_elem(sk_stg_map)", + "err:%d errno:%d\n", err, errno)) + goto done; + } + if (settcpca(lfd, tcp_ca) || settcpca(fd, tcp_ca) || settimeo(lfd) || settimeo(fd)) goto done; @@ -149,6 +158,16 @@ static void do_test(const char *tcp_ca) CHECK(bytes != total_bytes, "recv", "%zd != %u nr_recv:%zd errno:%d\n", bytes, total_bytes, nr_recv, errno); + if (sk_stg_map) { + int tmp_stg; + + err = bpf_map_lookup_elem(bpf_map__fd(sk_stg_map), &fd, + &tmp_stg); + CHECK(!err || errno != ENOENT, + "bpf_map_lookup_elem(sk_stg_map)", + "err:%d errno:%d\n", err, errno); + } + wait_thread: WRITE_ONCE(stop, 1); pthread_join(srv_thread, &thread_ret); @@ -175,7 +194,7 @@ static void test_cubic(void) return; } - do_test("bpf_cubic"); + do_test("bpf_cubic", NULL); bpf_link__destroy(link); bpf_cubic__destroy(cubic_skel); @@ -197,7 +216,10 @@ static void test_dctcp(void) return; } - do_test("bpf_dctcp"); + do_test("bpf_dctcp", dctcp_skel->maps.sk_stg_map); + CHECK(dctcp_skel->bss->stg_result != expected_stg, + "Unexpected stg_result", "stg_result (%x) != expected_stg (%x)\n", + dctcp_skel->bss->stg_result, expected_stg); bpf_link__destroy(link); bpf_dctcp__destroy(dctcp_skel); diff --git a/tools/testing/selftests/bpf/progs/bpf_dctcp.c b/tools/testing/selftests/bpf/progs/bpf_dctcp.c index 127ea762a062..5c1fc584f3ae 100644 --- a/tools/testing/selftests/bpf/progs/bpf_dctcp.c +++ b/tools/testing/selftests/bpf/progs/bpf_dctcp.c @@ -6,6 +6,7 @@ * the kernel BPF logic. */ +#include <stddef.h> #include <linux/bpf.h> #include <linux/types.h> #include <bpf/bpf_helpers.h> @@ -14,6 +15,15 @@ char _license[] SEC("license") = "GPL"; +static volatile int stg_result; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, int); +} sk_stg_map SEC(".maps"); + #define DCTCP_MAX_ALPHA 1024U struct dctcp { @@ -43,12 +53,18 @@ void BPF_PROG(dctcp_init, struct sock *sk) { const struct tcp_sock *tp = tcp_sk(sk); struct dctcp *ca = inet_csk_ca(sk); + int *stg; ca->prior_rcv_nxt = tp->rcv_nxt; ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA); ca->loss_cwnd = 0; ca->ce_state = 0; + stg = bpf_sk_storage_get(&sk_stg_map, (void *)tp, NULL, 0); + if (stg) { + stg_result = *stg; + bpf_sk_storage_delete(&sk_stg_map, (void *)tp); + } dctcp_reset(tp, ca); } -- 2.17.1 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage to bpf_tcp_ca 2020-03-19 23:50 ` [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage " Martin KaFai Lau @ 2020-03-20 3:49 ` Yonghong Song 2020-03-20 5:33 ` Martin KaFai Lau 0 siblings, 1 reply; 6+ messages in thread From: Yonghong Song @ 2020-03-20 3:49 UTC (permalink / raw) To: Martin KaFai Lau, bpf Cc: Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev On 3/19/20 4:50 PM, Martin KaFai Lau wrote: > This patch adds test to exercise the bpf_sk_storage_get() > and bpf_sk_storage_delete() helper from the bpf_dctcp.c. > > Signed-off-by: Martin KaFai Lau <kafai@fb.com> > --- > .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 28 +++++++++++++++++-- > tools/testing/selftests/bpf/progs/bpf_dctcp.c | 16 +++++++++++ > 2 files changed, 41 insertions(+), 3 deletions(-) > > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > index 8482bbc67eec..9aaecce0bc3c 100644 > --- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > @@ -11,6 +11,7 @@ > static const unsigned int total_bytes = 10 * 1024 * 1024; > static const struct timeval timeo_sec = { .tv_sec = 10 }; > static const size_t timeo_optlen = sizeof(timeo_sec); > +static int expected_stg = 0xeB9F; > static int stop, duration; > > static int settimeo(int fd) > @@ -88,7 +89,7 @@ static void *server(void *arg) > return NULL; > } > > -static void do_test(const char *tcp_ca) > +static void do_test(const char *tcp_ca, const struct bpf_map *sk_stg_map) > { > struct sockaddr_in6 sa6 = {}; > ssize_t nr_recv = 0, bytes = 0; > @@ -110,6 +111,14 @@ static void do_test(const char *tcp_ca) > return; > } > > + if (sk_stg_map) { > + err = bpf_map_update_elem(bpf_map__fd(sk_stg_map), &fd, > + &expected_stg, BPF_NOEXIST); > + if (CHECK(err, "bpf_map_update_elem(sk_stg_map)", > + "err:%d errno:%d\n", err, errno)) > + goto done; > + } > + > if (settcpca(lfd, tcp_ca) || settcpca(fd, tcp_ca) || > settimeo(lfd) || settimeo(fd)) > goto done; > @@ -149,6 +158,16 @@ static void do_test(const char *tcp_ca) > CHECK(bytes != total_bytes, "recv", "%zd != %u nr_recv:%zd errno:%d\n", > bytes, total_bytes, nr_recv, errno); Should the control go to "wait_thread" here if failure? > > + if (sk_stg_map) { > + int tmp_stg; > + > + err = bpf_map_lookup_elem(bpf_map__fd(sk_stg_map), &fd, > + &tmp_stg); > + CHECK(!err || errno != ENOENT, > + "bpf_map_lookup_elem(sk_stg_map)", > + "err:%d errno:%d\n", err, errno); > + } > + > wait_thread: > WRITE_ONCE(stop, 1); > pthread_join(srv_thread, &thread_ret); > @@ -175,7 +194,7 @@ static void test_cubic(void) > return; > } > > - do_test("bpf_cubic"); > + do_test("bpf_cubic", NULL); > > bpf_link__destroy(link); > bpf_cubic__destroy(cubic_skel); > @@ -197,7 +216,10 @@ static void test_dctcp(void) > return; > } > > - do_test("bpf_dctcp"); > + do_test("bpf_dctcp", dctcp_skel->maps.sk_stg_map); > + CHECK(dctcp_skel->bss->stg_result != expected_stg, > + "Unexpected stg_result", "stg_result (%x) != expected_stg (%x)\n", > + dctcp_skel->bss->stg_result, expected_stg); > > bpf_link__destroy(link); > bpf_dctcp__destroy(dctcp_skel); > diff --git a/tools/testing/selftests/bpf/progs/bpf_dctcp.c b/tools/testing/selftests/bpf/progs/bpf_dctcp.c > index 127ea762a062..5c1fc584f3ae 100644 > --- a/tools/testing/selftests/bpf/progs/bpf_dctcp.c > +++ b/tools/testing/selftests/bpf/progs/bpf_dctcp.c > @@ -6,6 +6,7 @@ > * the kernel BPF logic. > */ > > +#include <stddef.h> > #include <linux/bpf.h> > #include <linux/types.h> > #include <bpf/bpf_helpers.h> > @@ -14,6 +15,15 @@ > > char _license[] SEC("license") = "GPL"; > > +static volatile int stg_result; "int stg_result = 0;" should work too. > + > +struct { > + __uint(type, BPF_MAP_TYPE_SK_STORAGE); > + __uint(map_flags, BPF_F_NO_PREALLOC); > + __type(key, int); > + __type(value, int); > +} sk_stg_map SEC(".maps"); > + > #define DCTCP_MAX_ALPHA 1024U > > struct dctcp { > @@ -43,12 +53,18 @@ void BPF_PROG(dctcp_init, struct sock *sk) > { > const struct tcp_sock *tp = tcp_sk(sk); > struct dctcp *ca = inet_csk_ca(sk); > + int *stg; > > ca->prior_rcv_nxt = tp->rcv_nxt; > ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA); > ca->loss_cwnd = 0; > ca->ce_state = 0; > > + stg = bpf_sk_storage_get(&sk_stg_map, (void *)tp, NULL, 0); > + if (stg) { > + stg_result = *stg; > + bpf_sk_storage_delete(&sk_stg_map, (void *)tp); > + } > dctcp_reset(tp, ca); > } > > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage to bpf_tcp_ca 2020-03-20 3:49 ` Yonghong Song @ 2020-03-20 5:33 ` Martin KaFai Lau 0 siblings, 0 replies; 6+ messages in thread From: Martin KaFai Lau @ 2020-03-20 5:33 UTC (permalink / raw) To: Yonghong Song Cc: bpf, Alexei Starovoitov, Daniel Borkmann, kernel-team, netdev On Thu, Mar 19, 2020 at 08:49:22PM -0700, Yonghong Song wrote: > > > On 3/19/20 4:50 PM, Martin KaFai Lau wrote: > > This patch adds test to exercise the bpf_sk_storage_get() > > and bpf_sk_storage_delete() helper from the bpf_dctcp.c. > > > > Signed-off-by: Martin KaFai Lau <kafai@fb.com> > > --- > > .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 28 +++++++++++++++++-- > > tools/testing/selftests/bpf/progs/bpf_dctcp.c | 16 +++++++++++ > > 2 files changed, 41 insertions(+), 3 deletions(-) > > > > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > > index 8482bbc67eec..9aaecce0bc3c 100644 > > --- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c > > @@ -11,6 +11,7 @@ > > static const unsigned int total_bytes = 10 * 1024 * 1024; > > static const struct timeval timeo_sec = { .tv_sec = 10 }; > > static const size_t timeo_optlen = sizeof(timeo_sec); > > +static int expected_stg = 0xeB9F; > > static int stop, duration; > > static int settimeo(int fd) > > @@ -88,7 +89,7 @@ static void *server(void *arg) > > return NULL; > > } > > -static void do_test(const char *tcp_ca) > > +static void do_test(const char *tcp_ca, const struct bpf_map *sk_stg_map) > > { > > struct sockaddr_in6 sa6 = {}; > > ssize_t nr_recv = 0, bytes = 0; > > @@ -110,6 +111,14 @@ static void do_test(const char *tcp_ca) > > return; > > } > > + if (sk_stg_map) { > > + err = bpf_map_update_elem(bpf_map__fd(sk_stg_map), &fd, > > + &expected_stg, BPF_NOEXIST); > > + if (CHECK(err, "bpf_map_update_elem(sk_stg_map)", > > + "err:%d errno:%d\n", err, errno)) > > + goto done; > > + } > > + > > if (settcpca(lfd, tcp_ca) || settcpca(fd, tcp_ca) || > > settimeo(lfd) || settimeo(fd)) > > goto done; > > @@ -149,6 +158,16 @@ static void do_test(const char *tcp_ca) > > CHECK(bytes != total_bytes, "recv", "%zd != %u nr_recv:%zd errno:%d\n", > > bytes, total_bytes, nr_recv, errno); > > Should the control go to "wait_thread" here if failure? Thanks for the review! I did think about that. I did not bail on this because the sk_stg_map check below does not depend on the about check. Hence, I didn't bail here. I moved the sk_stg_map test to the very bottom is for this reason also. Since you asked, I think it makes sense to go back to my first approach which is to do the below test immediately after connect() and just bail there. I will also take this chance to postpone the thread creation after connect(). > > > + if (sk_stg_map) { > > + int tmp_stg; > > + > > + err = bpf_map_lookup_elem(bpf_map__fd(sk_stg_map), &fd, > > + &tmp_stg); > > + CHECK(!err || errno != ENOENT, > > + "bpf_map_lookup_elem(sk_stg_map)", > > + "err:%d errno:%d\n", err, errno); > > + } > > + > > wait_thread: > > WRITE_ONCE(stop, 1); > > pthread_join(srv_thread, &thread_ret); > > @@ -175,7 +194,7 @@ static void test_cubic(void) > > return; > > } > > - do_test("bpf_cubic"); > > + do_test("bpf_cubic", NULL); > > bpf_link__destroy(link); > > bpf_cubic__destroy(cubic_skel); > > @@ -197,7 +216,10 @@ static void test_dctcp(void) > > return; > > } > > - do_test("bpf_dctcp"); > > + do_test("bpf_dctcp", dctcp_skel->maps.sk_stg_map); > > + CHECK(dctcp_skel->bss->stg_result != expected_stg, > > + "Unexpected stg_result", "stg_result (%x) != expected_stg (%x)\n", > > + dctcp_skel->bss->stg_result, expected_stg); > > bpf_link__destroy(link); > > bpf_dctcp__destroy(dctcp_skel); > > diff --git a/tools/testing/selftests/bpf/progs/bpf_dctcp.c b/tools/testing/selftests/bpf/progs/bpf_dctcp.c > > index 127ea762a062..5c1fc584f3ae 100644 > > --- a/tools/testing/selftests/bpf/progs/bpf_dctcp.c > > +++ b/tools/testing/selftests/bpf/progs/bpf_dctcp.c > > @@ -6,6 +6,7 @@ > > * the kernel BPF logic. > > */ > > +#include <stddef.h> > > #include <linux/bpf.h> > > #include <linux/types.h> > > #include <bpf/bpf_helpers.h> > > @@ -14,6 +15,15 @@ > > char _license[] SEC("license") = "GPL"; > > +static volatile int stg_result; > > "int stg_result = 0;" should work too. will use. ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-03-20 5:34 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-03-19 23:49 [PATCH bpf-next 0/2] bpf: Add bpf_sk_storage support to bpf_tcp_ca Martin KaFai Lau 2020-03-19 23:50 ` [PATCH bpf-next 1/2] " Martin KaFai Lau 2020-03-20 3:39 ` Yonghong Song 2020-03-19 23:50 ` [PATCH bpf-next 2/2] bpf: Add tests for bpf_sk_storage " Martin KaFai Lau 2020-03-20 3:49 ` Yonghong Song 2020-03-20 5:33 ` Martin KaFai Lau
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